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United States Patent | 5,347,350 |
Nakahata ,   et al. | September 13, 1994 |
A sheet feeder includes a feeder for feeding a sheet, a cassette for containing a plurality of stacks of small sized sheets side by side therein, the cassette including a plurality of biasing members for biasing the respective stacks of small sized sheets upwards so as to bring uppermost sheets of the respective stacks into contact with the feeder, a plurality of sheet detectors arranged in positions corresponding to the respective stacks of sheets for detecting the height of the respective stacks of sheets contained in the cassette, and a controller responsive to the plurality of sheet detectors for determining the absence of sheet in the cassette when at least one of the plurality of sheet detectors detects that the height of the stack has become lower than a predetermined height, and stopping a sheet feeding operation. This sheet feeder prevents the transfer device of an image forming apparatus from being smeared due to the fact that the small sized sheet is fed from only one stack.
Inventors: | Nakahata; Akinobu (Sakai, JP); Kubota; Hiroshi (Osaka, JP); Migita; Kouji (Sakai, JP); Fuchi; Masami (Neyagawa, JP); Oda; Kenji (Toyonaka, JP); Makiura; Yoshinori (Kawachinagano, JP); Yamaguchi; Katsuhide (Takatsuki, JP) |
Assignee: | Mita Industrial Co., Ltd. (Osaka, JP) |
Appl. No.: | 127469 |
Filed: | September 24, 1993 |
Aug 28, 1991[JP] | 3-215690 | |
Sep 03, 1991[JP] | 3-223106 |
Current U.S. Class: | 399/23; 271/9.03; 271/153; 271/258.02; 271/265.01; 399/393 |
Intern'l Class: | G03G 015/00; G03G 021/00 |
Field of Search: | 355/203,204,208,209,308,309,311 271/9,110,152,153,167,258 |
H21 | Feb., 1986 | Schieck. | |
4229113 | Oct., 1980 | Anderson et al. | |
4472049 | Sep., 1984 | Honma et al. | 355/206. |
4524691 | Jun., 1985 | Miller. | |
4535463 | Aug., 1985 | Ito et al. | 271/110. |
4603846 | Aug., 1986 | Miles. | |
4733310 | Mar., 1988 | Kapp et al. | |
4860055 | Aug., 1989 | Ohira et al. | 355/308. |
4991830 | Feb., 1991 | Yamanaka | 271/9. |
5076562 | Dec., 1991 | Sai et al. | 271/9. |
5102112 | Apr., 1992 | Takahashi | 271/9. |
5104111 | Apr., 1992 | Matsuda et al. | 271/110. |